Hexarhopalus (Hexarhopalus) yunnanensis, Jiang & Li & Ji & Engel & Wang, 2021

Jiang, Ri-Xin, Li, Ze-Chuan, Ji, Quan-Yu, Engel, Michael S. & Wang, Shuo, 2021, Three new species of the genus Hexarhopalus Fairmaire, 1891 (Coleoptera, Tenebrionidae: Cnodalonini) from China, Zootaxa 5004 (4), pp. 587-597 : 588-590

Hexarhopalus (Hexarhopalus) yunnanensis sp. nov.

( Figs 1–3 )

Type material. Holotype: CHINA: ♂, labeled ‘China: Yunnan, Hani-Yi Autonomous Prefecture of Honghe (ȗ河 ú尼ŭ彝ŭss治州), Gejiu City (个fi市), H: 1693m, 22.VIII.2020, local leg.’ ( MHBU) . Paratypes: CHINA: 2 ♂♂, 3 ♀♀ , same label data as the holotype (1 ♂, 1 ♀, MHBU; 1 ♂, 1 ♀, MYNU; 1 ♀, JQYC) .

Description. Male ( Figs 1A , 2 , 3A–F ): Body oval, strongly convex, black and dull.

Head ( Fig. 2A ) transverse, widest across compound eyes. Vertex finely covered with small punctures and each puncture bearing a short, thin seta. Genae and epistoma covered with denser punctures and setae in respect to punctures and setae on vertex. Labrum dark brown, narrower than epistoma, covered with bristles of medium length in its apical portion. Antennal tubercles weakly prominent, antenna ( Fig. 2C ) nearly as long as head plus pronotum, club constituted by four apical antennomeres. Relative lengths of antennomeres: 0.63: 0.17: 0.67: 0.50: 0.50: 0.50: 0.43: 0.40: 0.37: 0.37: 0.63; relative widths of antennomeres: 0.33: 0.27: 0.30: 0.30: 0.30: 0.33: 0.43: 0.47: 0.47: 0.47: 0.50. Antennomere I slightly expanded; antennomere II shortest, wider than long; antennomere III longest, more than three times as long as antennomere II, antennomeres IV–VI similar, shorter than antennomere III, antennomere VII expanded near apex, antennomere VIII slightly longer than wide, antennomeres IX–X about as long as wide, antennomere XI with apex rounded.

Pronotum ( Fig. 2A ) about as long as wide, widest at middle; dorsal surface covered with dense small punctures and short setae; disc with irregular rugosity; mediolongitudinal sulcus visible and delineated by irregular rugosity; pronotal groove thin and not obvious basally, absent in anterior part, and wide and shallow at lateral margin ( Fig. 2B ). Prosternum distinctly raised before procoxae, surface wrinkled with sparse short setae; apex of prosternal process rounded.

Elytra ovoid, about 1.5× longer than wide in dorsal view, humerus strongly narrowed, widest at apical 1/3, disc with regular rows of strong foveolate punctures and irregular rugosity; mesoscutellum transverse, nearly triangular; wings completely reduced.

Metaventrite and abdomen finely covered with short thin setae and dense large punctures; median sulcus distinct, extending from anterior margin to ca. 2/3 of metaventrite length. Abdominal ventrite I longest, about as long as sum of ventrites III and IV; ventrite II longer than metaventrite III; metaventrites III and IV distinctly concave; ventrite V shorter than combined lengths of ventrites III and IV, apex rounded; apical margin of abdominal ventrite VIII ( Fig. 3D ) medially impressed, posterior and lateral margins bearing long setae.

Femora claviform medially, strongly expanded in distal halves; all tibiae covered with brown setae apically; pro- and mesotibiae slightly curved, metatibia straight; tarsomeres simple, apical pro- and mesotarsomere about as long as combined lengths of proximal four tarsomeres, apical metatarsomere slightly shorter than combined lengths of proximal three metatarsomeres.

Aedeagus ( Figs 3A–C ) symmetrical in dorsal view, distinctly curvedprofile; spiculum gastrale ( Fig. 3E ) asymmetrical, short, with large apical lobes.

Measurements: BL 14.7–16.5 mm, HL 1.6–1.9 mm, HW 3.3–3.6 mm, PL 4.2–4.9 mm, PW 4.8–5.0 mm, EL 8.9–9.7 mm, EW 7.3–7.5 mm.

Female ( Fig. 1B ): Similar to male. Posterior margin of ventrite VIII ( Fig. 3F ) rounded and covered with sparse long setae. Spiculum ( Fig. 3F ) slightly tortuous, apex rounded and slightly dilated. Apex of ovipositor ( Fig. 3G–H ) with two long and two short setae.

Measurements: BL 15.0– 15.3 mm, HL 1.8–1.9 mm, HW 3.2–3.3 mm, PL 4.2–4.3 mm, PW 4.4–4.5 mm, EL 9.0– 9.2 mm, EW 6.9–7.2 mm.

Differential diagnosis. The new species is quite different from all other known Chinese species of Hexarhopalus owing to the oval profile of the body and the dorsal integument covered with irregular rugosity. However, H. (H.) yunnanensis sp. nov. resembles H. (H.) tuberculatus (Pic, 1928) from Laos in its general habitus, with both species having an overally oval profile to the body. Nonetheless, the two species can be separated on the basis of their different integumental sculpturing on the pronotum and elytra — the pronotum and elytra of H. (H.) tuberculatus are covered with differently sized tuberculation, while the new species is covered with irregular rugosity. The new species is more or less similar to H. (H.) sculptilis Kaszab, 1960 from Myanmar, both of them with a somewhat stubby body, but the latter with a wide and deep groove at the base of the pronotum, while the groove is much shallower in H. (H.) yunnanensis sp. nov..

Distribution. China: Yunnan.

Biology. Adults of this species can be collected on tree trunks at night, while during the day, they are hidden under tree bark and difficult to find ( Fig. 8 ).

Etymology. The specific epithet refers to the type locality, Yunnan Province; adjective.

Figures

FIGURE 1. Dorsal habitus of H. (H.) yunnanensis sp. nov. A. Male; B. Female.

FIGURE 2. Diagnostic features of H. (H.) yunnanensis sp. nov., male. A. Head and pronotum; B. Lateral groove of pronotum; C. Right antenna.

FIGURE 3. Diagnostic features of H. (H.) yunnanensis sp. nov. (A–E. Male; F–H. Female). A. Aedeagus, dorsal view; B. Same, lateral view; C. Same, ventral view; D. Abdominal ventrite VIII; E. Spiculum gastrale; F. Ventrite VIII of female and spiculum; G. Ovipositor; H. Same, apical part.

FIGURE 8. A. General environment of the type locality of H. (H.) yunnanensis sp. nov.; B & C. Live individuals photographed in nature.